The present invention relates to sheet materials which are disposable and suitable for protecting a supporting surface from various articles and/or substances placed thereon. The present invention further relates to such sheet materials which are also capable of absorbing and/or containing various liquids which may be carried by or exuded from such various articles and/or substances and protecting the supporting structure from these liquids.
Sheet-like materials for use in protecting objects or substances from a supporting surface, and/or protecting supporting surfaces from objects or substances, are well known in the art. Such materials can be utilized to provide a permanent form of protection, but most commonly are situation- or task-oriented and are only required or utilized for a limited period of time and then disposed of.
Protective materials having durability, such as cut-resistance, shred-resistance and/or wear resistance have been used for many applications. For instance, protective materials can be used as cutting boards to cover countertops during food preparation, such as when cutting meats or vegetables for cooking. Such protective materials can protect the food item from contacting contaminants which may reside on the support surface, such as a countertop. In addition, such materials can also protect the support surface from physical damage from a cutting tool, as well as from contamination from the food item being prepared.
However, many materials which are protective are not absorbent. For instance, a rigid plastic cutting board will not absorb juices from food items, and these juices may run off the cutting board and soil the countertop or support surface. In addition, many such materials are not flexible, and thus are not easily stored, manipulated, and disposed. Also, because many rigid cutting boards are not intended to be disposed after use, they require cleaning after each use.
For this reason, many materials which are highly cut-, shred-, and abrasion resistant are less than desirable due to the lack of flexibility and conformability typically inherent with such materials.
The reverse is also true, as many materials, such as paper-like materials, can exhibit high absorbency, flexibility, and disposability. However, such materials typically lose a significant amount of strength when wet, and thus cannot adequately protect a support surface from cutting forces. Also, such materials are not typically shred-resistant and thus, if used as a cutting board, particles from the material may transfer to the food item being prepared.
Thus, the consumer is faced with a paradox in selecting an appropriate sheet material for use in such a food preparation scenario. Sheet materials which are comparatively high in absorbency, such as paper-based materials, typically are comparatively low in shred- and cut-resistance in a wetted state, while those which are comparatively high in cut-resistance, such as plastic sheet materials, are comparatively low in absorbency.
For this reason, it would be desirable to provide such a sheet material which, while durable in use, may be so readily and economically manufactured so as to be disposed of after use.
In recognition of these issues, certain composite and/or laminate materials have been developed which combine components exhibiting each of the desirable properties into a coherent structure with overall properties generally intermediate to those of each material separately. While such materials may be suitable for certain applications, the points or regions of joinder between diverse materials frequently become points or regions of vulnerability to detachment when the sheet material is subjected to cutting or abrasion forces or repeated flexing under in-use conditions.
Accordingly, it would be desirable to provide multiple diverse properties such as cut resistance, abrasion resistance, and flexibility in a unitary material structure. It would also be desirable to provide such a material which is durable in use. It would further be desirable to provide such a material which may be readily and economically manufactured so that it can be disposed of after a single use, if so desired.
Polymeric fibers have previously been utilized as a binder and strengthening agent in paper structures. Typically, in such paper structures, fibers made from hydrophobic polymers are added to paper fluff during paper formation. During drying of the mixture, the polymeric fibers flow and coat the surrounding paper fibers locking the paper fibers into the structure and significantly reducing the overall absorbency of the resulting structure. While the amount of polymer fiber could be reduced from the mixture to increase absorbency, such a solution compromises the cut-resistance and shred-resistance of the structure. Thus, one problem with such structures is that the amount of polymer fibers required to achieve adequate cut-resistance and/or shred-resistance significantly reduces the absorbency of the structure.
Accordingly, it would be desirable to provide a sheet material which is both comparatively high in absorbency and comparatively high in shred- and cut-resistance. It is also desirable to provide such a material that is also relatively thin, light, and flexible so as to be readily disposable, and easily dispensed, stored, and manipulated. In addition, it is desirable to provide such sheet materials which, while durable in use, can be economically manufactured so as to justify their disposal after each use.
It is an object of the present invention to obviate the above-described problems.
Another object of the present invention is to provide a disposable and protective cutting sheet with a substantially smooth cutting surface.
It is a further object of the present invention to provide a sheet material that is light-weight, absorbent, cut-resistant, and shred-resistant.
Yet another object of the present invention is to provide a sheet material that can be used to slice food items while resisting wear from the cutting tool and absorbing juices from the food item.
A further object of the present invention is to provide a sheet material that is resistant to shredding and can absorb significant amounts of liquid produced by food items.
Another object of the present invention is to provide a cut-resistant and absorbent sheet material that is readily disposable.
Yet another object of the present invention is to provide a cut-resistant and absorbent, sheet material that is easily foldable.
A further object of the present invention is to provide an absorbent, cut- and shred-resistant sheet material that does not have a plastic-like appearance.
It is another object of the present invention to provide a protective and absorbent sheet material that can provide an indication of whether it has already been used.
The present invention encompasses a multi-purpose sheet material comprising a web of absorbing fibers. The web has a polymer containing layer comprising discontinuous, heat-bonded particles. The particles have an average diameter of from about 100 nanometer to about 1000 nanometer. The web comprises of from about 0.5 g/m2 to about 75 g/m2 of heat-bonded particles and, has a dry basis weight of from about 200 lb/3000 ft2 to about 400 lb/3000 ft2.
The present invention also encompasses a method for making a multi-purpose sheet by forming a web of absorbent fibers with a dry basis weight of from about 200 lb/3000 ft2 to about 400 lb/3000 ft2 and applying a polymeric material comprising heat bondable particles having an average diameter of from about 100 nanometer to about 1000 nanometer. The web is then heated until the polymeric material melts and then subsequently cooled.